The present invention relates to a fixing tool used to package an electronic component, a cable, or the like on the chassis of an electronic device or the like and, more particularly, to a fixing tool that can be removed from the upper surface of the chassis easily.
When assembling an electronic device, electronic components must be attached to an assembly board such as a panel, chassis, board, or the like (which will be referred to as a chassis hereinafter), and wiring components such as cables must be extended on the board. A mounting component is used for this purpose. For example, when a plurality of cables are to be extended parallel to each other along the surface of a chassis, a cable tie which ties the plurality of cables together and attaches them on the chassis is used. FIG. 12 shows an example of a conventional cable tie. A cable tie 1C has a band portion 11 with one free end that ties a plurality of cables together, and a locking portion 12 to which the proximal end of the band portion 11 is connected and which has engaging teeth to fit with sawteeth (not shown) of the band portion 11, when the band portion 11 is inserted in the locking portion 12 from its distal end, so that removal of the band portion 11 is prevented. The band portion 11 and locking portion 12 have the same arrangements as those of the cable tie of an embodiment to be described later, and a detailed description thereof will be omitted.
The locking portion 12 has a fitting portion 30 on its lower surface. The fitting portion 30 has a pair of fitting pieces 32 overhanging like arrowheads from the two sides of its post 31 projecting downward. When the fitting pieces 32 are inserted in a through hole 3 formed in a chassis 2 from the upper surface of the chassis 2, the pair of fitting pieces 32 are reduced in diameter by their elasticity to extend through the through hole 3. After passing through the through hole 3, the fitting pieces 32 elastically restore to enlarge in diameter, so that steps 32a formed on the terminal ends of the fitting pieces 32 fit with the inner edge of the through hole 3. A pair of inverted-V-shaped leg pieces 34 which oppose the fitting pieces 32 abut against the upper surface of the chassis 2, so that the steps 32a and through hole 3 are held fitted with each other. As an example of a fixing tool that has such a fitting portion, for example, one described in Patent Reference 1 (Japanese Patent Laid-Open No. 9-242936) is available.
In recent years, in home electric appliances, OA devices, automobiles, and electronic devices as a whole, environmentally friendly products must be sold to solve environmental issues. Along with this demand, for example, a printed board or connecting wires built in an electronic device must be able to be disassembled from the chassis, panel, or the like of the electronic device. Particularly, to facilitate the disassembling operation, the printed board or wiring lines must be disassembled easily without using any tools. With the structure of the conventional fitting portion shown in FIG. 12, however, the fitting pieces 32 must be reduced in diameter by using hands or a tool, and be extracted from the through hole 3 of the chassis 2. In this case, since the fitting pieces 32 are small and difficult to hold, they are difficult to handle. Also, the fitting pieces 32 must be reduced in diameter on the lower surface side of the chassis 2, leading to poor workability.
Regarding this issue, if the fitting pieces 32 are designed and manufactured to have low elasticity, they can be reduced in diameter easily, and can be removed from the chassis 2 easily. However, the poor operability on the lower surface side of the chassis 2 cannot be improved. If the elasticity of the fitting pieces 32 is merely decreased, when an external force acts on the fitting pieces 32, the fitting pieces 32 are likely to deform easily and be reduced in diameter easily. Then, the fixing tool may drop from the chassis 2 easily.